Mobile information terminal

ABSTRACT

Provided is a mobile information terminal that performs data transmission and reception, the data transmission and reception including video data reception. The mobile information terminal includes a communication management execution module that obtains a communication amount of data transmitted and received by the mobile information terminal in a predetermined period, and a remote viewing execution module that compares the obtained communication amount to a preset predetermined value and makes an image quality of the video data selectable according to a relationship between the obtained communication amount and the predetermined value.

TECHNICAL FIELD

The present invention relates to a mobile information terminal.

BACKGROUND ART

A mobile information terminal such as a mobile phone, a smartphone, or atablet terminal is generally used for content viewing. For example, withthe use of a content distribution service, it is possible for a user toview, for example, video content (moving image, still image) or audiocontent downloaded or streaming from a server on a network to a mobileinformation terminal. Particularly, contents such as moving images havebecome significantly larger in size in recent years as the resolution ofthe contents becomes higher.

However, the following Patent Literature 1 describes that “to becomesmartphone users, most of such users tend to subscribe to flat-ratecommunication charge plans (generally called “Fake-hodai”). These plansallow users to view web sites or video sites without worrying about thecost, thereby accelerating the increase in data communication amount. Onthe other hand, a large difference in data communication amount arisesamong users, and, in reality, a significant amount of use by some heavyusers pushes up the entire communication amount. Thus, flat-rate chargesare increased for facility enhancement, which will result in unfairnessamong users. Accordingly, some of the carriers have begun to takemeasures for reducing the entire data communication amount by limiting abandwidth used by each of the users who have performed communication ofextremely large amount of data.”

CITATION LIST Patent Literature

-   Patent Literature 1: Japanese Unexamined Patent Application    Publication No. 2013-058994A

SUMMARY OF INVENTION Technical Problem

In fact, some of the mobile phone carriers in Japan impose limitationson communication speed for the purposes of, for example, preventingtheir lines from being occupied by some heavy users. The purpose of suchlimitations on communication speed is to force a data communicationspeed to be a lower speed when the total data communication amountthrough mobile phone network communication in a communication systemsuch as wideband code division multiple access (W-CDMA) (registeredtrademark) or long term evolution (LTE) in a predetermined periodexceeds a predetermined value. For example, once the total datacommunication amount in a month exceeds 7.0 GB, the subsequent datacommunication speed is limited to less than or equal to 128 kbps withinthe month. That is, it can be said that the data capacity within whichhigh-speed data communication is possible is predetermined for eachpredetermined period in mobile phone network communication systems ofthe mobile phone carriers.

Thus, a user uses the above-described content distribution service to,for example, download large moving-image content or view such content inthe form of streaming data at the early time of the predetermined periodand uses up the data communication capacity within which high-speed datacommunication is possible, the subsequent use of the service may becomeinconvenient for the user. Therefore, when the content distributionservice that requires communication of large amount of data is used, itis desirable to perform communication control or the like that takes thedata communication amount into consideration. The Patent Literature 1describes a technique that imposes a limitation on data communicationamount, but it does not describe communication control based on a datacommunication amount.

An object of the present invention is to provide a mobile informationterminal that provides high usability when content viewing is performed.

Solution to Problem

The techniques described in the claims are used as means for solving theproblem described above.

Examples of the techniques used herein include a mobile informationterminal that performs data transmission and reception, the datatransmission and reception including video data reception. The mobileinformation terminal includes a communication management executionmodule that obtains a communication amount of data transmitted andreceived by the mobile information terminal in a predetermined period,and a remote viewing execution module that compares the obtainedcommunication amount to a preset predetermined value and makes an imagequality of the video data selectable according to a relationship betweenthe obtained communication amount and the predetermined value.

Advantageous Effects of Invention

Employing the present invention makes it possible to provide a mobileinformation terminal that provides high usability when content viewingis performed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating an example of a system configuration ofa communication system.

FIG. 2A is a diagram illustrating an example of a block configuration ofa mobile information terminal.

FIG. 2B is a diagram illustrating an example of a software configurationof the mobile information terminal.

FIG. 3 is a diagram illustrating an example of a block configuration ofa broadcast receiver.

FIG. 4 is a diagram illustrating an example of an operation sequenceperformed during the execution of a remote viewing function of themobile information terminal.

FIG. 5A is a diagram illustrating a display example of a basic screen ofthe mobile information terminal.

FIG. 5B is a diagram illustrating a display example of a program typeselection screen of the mobile information terminal.

FIG. 5C is a diagram illustrating a display example of a program guidescreen of the mobile information terminal.

FIG. 5D is a diagram illustrating a display example of a remote imagequality selection screen of the mobile information terminal.

FIG. 5E is a diagram illustrating a display example of a remote viewingscreen of the mobile information terminal.

FIG. 6A is a diagram illustrating an example of control of remoteviewing image quality according to a total data communication amount ofthe mobile information terminal.

FIG. 6B is a diagram illustrating an example of control of the remoteviewing image quality according to the total data communication amountof the mobile information terminal and a period.

FIG. 7A is a diagram illustrating an example of a display format of aremote image quality selection box that imposes a limitation on theselection thereof.

FIG. 7B is a diagram illustrating an example of a display format of theremote image quality selection box that does not impose a limitation onthe selection thereof.

FIG. 8 is a diagram illustrating a display example of a remote imagequality selection screen of the mobile information terminal includingviewable times.

DESCRIPTION OF EMBODIMENT

Examples of an embodiment of the present invention will be describedbelow with reference to the drawings.

System Configuration

FIG. 1 is a system configuration diagram illustrating an example of acommunication system including a mobile information terminal of thepresent example. The communication system of the present exampleincludes a mobile information terminal 100, a broadband network 200 suchas the Internet, an access point 200 a, a router 200 r, a mobile phonecommunication server 300, a base station 300 b of a mobile phonecommunication network, a broadcast receiver 400, an antenna 400 a, abroadcasting tower 400 t of a broadcasting station, and an additionalapplication server 500.

The mobile information terminal 100 has telephone communication (phonecall) and data transmission and reception capabilities via a mobilephone network, and a wireless communication capability using, forexample, Wi-Fi (registered trademark). The mobile information terminal100 is capable of connecting to the Internet 200 via the outdoor accesspoint 200 a or via the base station 300 b and mobile phone communicationserver 300 of the mobile phone communication network. In addition, themobile information terminal 100 is capable of communicating with eachserver on the Internet 200 for data transmission and reception.Additionally, the mobile information terminal 100 has a capability toplay back, for example, video content (moving image, still image) oraudio content obtained from each server on the Internet 200.

The mobile information terminal 100 may be, for example, a mobile phone,a smartphone, or a tablet terminal. The mobile information terminal 100may also be, for example, a personal digital assistant (PDA), a laptoppersonal computer (PC), or an electronic book reader. Furthermore, themobile information terminal 100 may be, for example, a digital stillcamera, a video camera capable of capturing videos, a mobile gameconsole, a navigation device, or any other mobile digital device.

The access point 200 a is connected with the Internet 200 through wiredcommunication and connected with the mobile information terminal 100through wireless communication such as Wi-Fi. This configuration allowsthe mobile information terminal 100 and each server on the Internet 200to mutually transmit and receive data via the access point 200 a.

The mobile phone communication server 300 is connected with the Internet200 and connected with the mobile information terminal 100 via the basestation 300 b. The mobile phone communication server 300 managestelephone communication (phone call) and data transmission andreception, via the mobile phone communication network, of the mobileinformation terminal 100 and allows data transmission and receptionthrough the communication between the mobile information terminal 100and each server on the Internet 200. The mobile information terminal 100and the base station 300 b may communicate with each other in the W-CDMAsystem, LTE system, or any other communication system.

The broadcast receiver 400 is a television receiver that receives anddisplays a digital broadcast wave transmitted from the broadcastingtower 400 t of the broadcasting station via the antenna 400 a. Thebroadcast receiver 400 may be, for example, an optical disc driverecorder such as a digital versatile disc (DVD) recorder, a magneticdisk drive recorder such as a hard disc drive (HDD) recorder, or a settop box (STB). The broadcast receiver 400 may also be, for example, aPC, a tablet terminal, or a game console that is capable of receiving adigital broadcast.

Note that the broadcast receiver 400 is capable of connecting with theInternet 200 via the in-house router 200 r and is capable ofcommunicating with each server on the Internet 200 for data transmissionand reception.

The router 200 r is connected with the Internet 200 through wiredcommunication and is connected with the broadcast receiver 400 throughwireless communication or wired communication. Furthermore, the router200 r may be connected with the mobile information terminal 100 throughwireless communication such as Wi-Fi. This configuration allows eachserver on the Internet 200, the broadcast receiver 400, and the mobileinformation terminal 100 to mutually transmit and receive data via therouter 200 r. Note that the broadcast receiver 400 and the mobileinformation terminal 100 may communicate directly, namely, not via therouter 200 r, with each other in a system such as BlueTooth (registeredtrademark) or near field communication (NFC).

The additional application server 500 is a known server that performs,for example, storage, management, and distribution of generalapplications, operation programs, and various contents and data. Theremay be more than one additional application server 500 on the Internet200.

Hardware Configuration of Mobile Information Terminal

FIG. 2A is a block diagram illustrating an example of the internalconfiguration of the mobile information terminal 100. The mobileinformation terminal 100 includes a main controller 101, a system bus102, a ROM 103, a RAM 104, a storage unit 110, a communication processor120, an extended interface 124, an operation unit 130, an imageprocessor 140, an audio processor 150, and a sensor 160.

The main controller 101 is a microprocessor unit that controls theentire mobile information terminal 100. The system bus 102 is a datacommunication channel for data transmission and reception between themain controller 101 and each operating block in the mobile informationterminal 100.

The read only memory (ROM) 103 is a memory in which a basic operationprogram, such as an operating system, and other operation programs arestored. For example, a rewritable ROM such as an electrically erasableprogrammable ROM (EEPROM) or a flash ROM is used. The random accessmemory (RAM) 104 serves as a work area during the execution of the basicoperation program or other operation programs. The ROM 103 and the RAM104 may be integrated with the main controller 101. Furthermore, the ROM103 may be constituted of some storage area in the storage unit 110rather than an independent element as illustrated in FIG. 2A.

The storage unit 110 stores, for example, operation programs andoperation setting values of the mobile information terminal 100, andpersonal information on the user of the mobile information terminal 100.In addition, an operation program downloaded from a network, variousdata created by the operation program, and the like can be stored in thestorage unit 110. Furthermore, content such as a moving image, stillimage, and audio downloaded from a network can be stored in the storageunit 110. Some area in the storage unit 110 may constitute part or allof the ROM 103. Furthermore, it is required that the storage unit 110retain the stored information even with no power supplied from outsideto the mobile information terminal 100. Therefore, for example, asemiconductor memory such as a flash ROM or a solid state drive (SSD),or a magnetic disk drive such as an HDD is used.

Note that the operation programs stored in the ROM 103 or the storageunit 110 may be updated or functionally extended through downloadingfrom each server on the Internet 200.

The communication processor 120 includes a local area network (LAN)communication unit 121, a mobile phone network communication unit 122,and an NFC communication unit 123. The LAN communication unit 121 isconnected with the Internet 200 via the outdoor access point 200 a orthe in-house router 200 r and performs data transmission and receptionwith each server on the Internet 200. The LAN communication unit 121 isconnected with the access point 200 a or the router 200 r throughwireless connection such as Wi-Fi. The mobile phone networkcommunication unit 122 performs telephone communication (phone call) anddata transmission and reception through wireless communication with thebase station 300 b of the mobile phone communication network. The mobilephone network communication unit 122 is connected with the base station300 b in a communication system such the W-CDMA system or the LTEsystem. The NFC communication unit 123 performs wireless communication,with the NFC communication unit 123 in close proximity to acorresponding reader/writer. The LAN communication unit 121, the mobilephone network communication unit 122, and the NFC communication unit 123are each provided with a coding circuit, a decoding circuit, an antenna,and the like. Furthermore, the communication processor 120 may beprovided with an additional communication unit such as a BlueToothcommunication unit or an infrared communication unit.

The extended interface 124 is a group of interfaces for extending thecapabilities of the mobile information terminal 100. The extendedinterface 124 includes, for example, a video/audio interface, auniversal serial bus (USB) interface, and a memory interface in thepresent example. The video/audio interface receives a video signal/audiosignal from an external video/audio output device, outputs a videosignal/audio signal to the external video/audio input device, and thelike. The USB interface is connected with, for example, a PC to performdata transmission and reception therewith. The USB interface may also beconnected with a keyboard or any other USB device. The memory interfaceis connected with a memory card or any other memory medium to performdata transmission and reception therewith.

The operation unit 130 is an instruction-input unit for a user to inputan operation instruction to the mobile information terminal 100. In thepresent example as illustrated in FIG. 5A, the operation unit 130includes a touch panel 130 t disposed on a display unit 141 so as tocover the display unit 141, and operation keys 130 k that are buttonswitches arranged. The operation unit 130 may include only one of thetouch panel 130 t and the operation keys 130 k. The mobile informationterminal 100 may be operated through, for example, a keyboard connectedto the extended interface 124. The mobile information terminal 100 maybe operated through a separate mobile terminal device connected throughwired communication or wireless communication. Furthermore, the displayunit 141 may be provided with the touch panel function.

The image processor 140 includes the display unit 141, an image signalprocessor 142, a first image input unit 143, and a second image inputunit 144. The display unit 141 is, for example, a display device such asa liquid crystal panel and provides image data processed by the imagesignal processor 142 to the user of the mobile information terminal 100.The image signal processor 142 is provided with a video RAM (notillustrated) and drives the display unit 141 on the basis of the imagedata input to the video RAM. The image signal processor 142 has acapability to perform, for example, format conversion, andsuperimposition of a menu or other on-screen display (OSD) signals asneeded. The first image input unit 143 and the second image input unit144 are camera units for converting light incident through a lens to anelectrical signal by using an electronic device such as a charge coupleddevice (CCD) or complementary metal oxide semiconductor (CMOS) sensor toobtain image data of surroundings or an object.

The audio processor 150 includes an audio output unit 151, an audiosignal processor 152, and an audio input unit 153. The audio output unit151 is a speaker that provides an audio signal processed by the audiosignal processor 152 to the user of the mobile information terminal 100.The audio input unit 153 is a microphone that converts, for example, auser's voice to audio data and inputs the audio data.

The sensor 160 is a group of sensors for detecting states of the mobileinformation terminal 100. The sensor 160 includes, in the presentexample, a global positioning system (GPS) receiver 161, a gyrosensor162, a magnetic field sensor 163, an acceleration sensor 164, anilluminance sensor 165, and a proximity sensor 166. The group of sensorsmakes it possible to detect, for example, a position, inclination,orientation, motion, ambient brightness, and proximity to surroundingobjects of the mobile information terminal 100. The mobile informationterminal 100 may further be provided with another sensor such as anatmospheric pressure sensor.

Note that although the configuration example of the mobile informationterminal 100 illustrated in FIG. 2A includes many components that arenot required for the present example, such as the sensor 160, aconfiguration even without these components does not impair the effectof the present example. Other components (not illustrated) such as adigital broadcast reception function or an electronic money settlementfunction may be added.

Software Configuration of Mobile Information Terminal

FIG. 2B is a software configuration diagram of the mobile informationterminal 100 of the present example. FIG. 2B illustrates an example ofsoftware configurations in the ROM 103, the RAM 104, and the storageunit 110. In the present example, a basic operation program 1001 andother operation programs are stored in the ROM 103, and a remote viewingprogram 1002, a communication management program 1003, a contentplayback program 1004, and other operation programs are stored in thestorage unit 110. Furthermore, the storage unit 110 includes a contentstorage area 1011 for storing content such as a moving image, stillimage, and audio, an authentication information storage area 1012 forstoring authentication information used for collaborative operation withan external device, and a various information storage area 1019 forstoring other various information.

The basic operation program 1001 stored in the ROM 103 is loaded in theRAM 104, and then the main controller 101 executes the loaded basicoperation program to configure a basic operation execution module 1101.Note that, for illustrating this state, the basic operation executionmodule 1101 is depicted inside the RAM 104 in FIG. 2B. The other modulesinside the RAM 104, which will be described below, are depicted in thesame way. The remote viewing program 1002, the communication managementprogram 1003, and the content playback program 1004 stored in thestorage unit 110 are loaded in the RAM 104, and then the main controller101 executes the loaded operation programs to configure respectivemodules, namely, a remote viewing execution module 1102, a communicationmanagement execution module 1103, and a content playback executionmodule 1104. The RAM 104 includes a temporary storage area 1109 fortemporarily retaining, for example, data generated during the executionof each operation program as needed.

For ease of explanation, a process in which the main controller 101loads, in the RAM 104, the basic operation program 1001 stored in theROM 103 and executes the loaded program to control each operating blockwill be described below as a process in which the basic operationexecution module 1101 controls each operating block. Other operationprograms will be described in a similar manner. The detail of eachoperation execution module will be described later.

Each of the operation programs may be pre-stored in the ROM 103 and/orthe storage unit 110 before product shipment. The program may beobtained from, for example, the additional application server 500 on theInternet 200 via the LAN communication unit 121 or the mobile phonenetwork communication unit 122 after product shipment. Each of theoperation programs stored in, for example, a memory card or optical discmay be obtained via the extended interface 124 or the like.

Hardware Configuration of Broadcast Receiver

FIG. 3 is a block diagram illustrating an example of the internalconfiguration of the broadcast receiver 400. The broadcast receiver 400includes a main controller 401, a system bus 402, a ROM 403, a RAM 404,a storage unit 410, a LAN communication unit 421, an extended interface424, a tuner/demodulator 431, a demultiplexer 432, a video decoder 433,an audio decoder 434, a subtitle decoder 435, a data broadcast receptionprocessor 436, a video superimposing unit 437, a code converter 440, avideo display unit 451, a speaker 452, a video output unit 453, and anaudio output unit 454.

The main controller 401 is a microprocessor unit that controls theentire broadcast receiver 400 according to a predetermined operationprogram. The system bus 402 is a data communication channel for datatransmission and reception between the main controller 401 and eachoperating block in the broadcast receiver 400.

The ROM 403 is a memory in which a basic operation program, such as anoperating system, and other operation programs are stored. For example,a rewritable ROM such as an EEPROM or a flash ROM is used. The RAM 404serves as a work area during the execution of the basic operationprogram or other operation programs.

The storage unit 410 stores, for example, operation programs andoperation setting values of the broadcast receiver 400, and personalinformation on the user of the broadcast receiver 400. In addition, anoperation program downloaded from a network, various data created by theoperation program, and the like can be stored in the storage unit 410.Furthermore, content such as a moving image, still image, and audioobtained from a broadcast wave or downloaded from a network can bestored in the storage unit 410. Some area in the storage unit 410 mayconstitute part or all of the ROM 403.

The LAN communication unit 421 is connected with the Internet 200 viathe in-house router 200 r and performs data transmission and receptionwith each server on the Internet 200. The connection with the router 200r may be a wired connection or may be a wireless connection such asWi-Fi. The LAN communication unit 421 is provided with a coding circuit,a decoding circuit, and the like. Furthermore, the broadcast receiver400 may be provided with an additional communication unit such as aBlueTooth communication unit, an NFC communication unit, or an infraredcommunication unit.

The tuner/demodulator 431 a and tuner/demodulator 431 b receive adigital broadcast wave from the broadcasting tower 400 t via the antenna400 a and tune in to (select) a channel for a service desired by theuser under the control of the main controller 401. Furthermore, thetuner/demodulator 431 a and tuner/demodulator 431 b demodulate abroadcast signal in the received digital broadcast wave to obtain atransport stream (TS). Note that the example illustrated in FIG. 3includes two tuner/demodulators. The tuner/demodulator 431 a andtuner/demodulator 431 b can be controlled independently. In thefollowing, the tuner/demodulator 431 a and tuner/demodulator 431 b arenot distinguished from each other and referred to as a tuner/demodulator431.

The demultiplexer 432 receives the TS output from the tuner/demodulator431 and demultiplexes the TS into data rows such as a video data row, anaudio data row, a subtitle data row, a program information data row, anda broadcast markup language (BML) data row. These data rows may be, forexample, in the form of an elementary stream (ES). The video decoder 433decodes the video data row input from the demultiplexer 432 and outputsvideo information. The audio decoder 434 decodes the audio data rowinput from the demultiplexer 432 and outputs audio information. Thesubtitle decoder 435 decodes the subtitle data row input from thedemultiplexer 432 and outputs subtitle information. The data broadcastreception processor 436 decodes the BML data row input from thedemultiplexer 432 to regenerate a BML document and executes the BMLdocument to output data broadcast screen information.

The video superimposing unit 437 receives the video information outputfrom the video decoder 433, the subtitle information output from thesubtitle decoder 435, and the data broadcast screen information outputfrom the data broadcast reception processor 436 and performs a processsuch as selection and/or superimposition. The video superimposing unit437 is provided with a video RAM (not illustrated), and the videodisplay unit 451 and the like are driven on the basis of the videoinformation input in the video RAM. Furthermore, the video superimposingunit 437 performs, for example, a scaling process, and a superimposingprocess, as needed, on electronic program guide (EPG) screen informationcreated on the basis of the program information data row output from thedemultiplexer 432 under the control of the main controller 401.

The code converter 440 performs a transcoding process on the TS outputfrom the tuner/demodulator 431, the ES output from the demultiplexer432, recorded content obtained from the storage unit 110, or the like toconvert, for example, a resolution, a bit rate, or a coding system.

The video display unit 451 is, for example, a display device such as aliquid crystal panel that provides, to the user of the broadcastreceiver 400, the video information subjected to the selection processand/or superimposing process by the video superimposing unit 437. Thespeaker 452 provides the audio information output from the audio decoder434 to the user of the broadcast receiver 400. The video output unit 453is a video output interface that outputs the video information subjectedto the selection process and/or superimposing process by the videosuperimposing unit 437. The audio output unit 454 is an audio outputinterface that outputs the audio information output from the audiodecoder 434.

Note that the video output unit 453 and audio output unit 454 are notessential components of the present example in a case where thebroadcast receiver 400 is, for example, a television receiver. The videodisplay unit 451 and speaker 452 are not essential components of thepresent example in a case where the broadcast receiver 400 is, forexample, a DVD recorder.

The extended interface 424 is a group of interfaces for extending thecapabilities of the broadcast receiver 400. The extended interface 424includes, for example, a video/audio interface, a USB interface, and amemory interface in the present example. The video/audio interfacereceives a video signal/audio signal from an external video/audio outputdevice, outputs a video signal/audio signal to the external video/audioinput device, and the like. The USB interface is connected with, forexample, a PC to perform data transmission and reception therewith. AnHDD may be connected to the USB interface to record a broadcast programor downloaded content. The USB interface may also be connected with akeyboard or any other USB device. The memory interface is connected witha memory card or any other memory medium to perform data transmissionand reception therewith.

Operation Sequence of Mobile Information Terminal

An operation of the mobile information terminal 100 of the presentexample will be described below.

Note that a description is given of a case where the mobile informationterminal 100 and the broadcast receiver 400 of the present example areprovided with a remote viewing function that makes a digital broadcastprogram or recorded content thereof viewable with, for example, asmartphone or a tablet terminal located away from home via the Internet200, such a digital broadcast program being received by, for example, anin-house television receiver or a DVD recorder.

Furthermore, in the present example, the data transmission and receptionbetween the mobile information terminal 100 and the Internet 200 isperformed by the mobile phone network communication unit 122 via themobile phone communication server 300 and the base station 300 b. Thisincludes a case where data transmission and reception using the LANcommunication unit 121 is impossible due to, for example, no accesspoint 200 a being located near the mobile information terminal 100.Furthermore, the data communication function provided by the mobilephone carrier for the mobile information terminal 100 of the presentexample has a capability to impose a limitation on communication speed.

FIG. 4 is an operation sequence diagram illustrating an example ofoperations performed during the execution of the remote viewing functionof the mobile information terminal 100. FIGS. 5A to 5E are screendisplay diagrams illustrating each operation screen displayed on thedisplay unit 141 of the mobile information terminal 100 during theexecution of the remote viewing function.

FIG. 5A is a screen display diagram illustrating an example of a basicscreen 141 a displayed on the display unit 141 of the mobile informationterminal 100. The basic screen 141 a is displayed upon the power to themobile information terminal 100 being turned on by pressing a power key130 k 1 or upon a home key 130 k 2 being pressed during the execution ofany application program. In the basic screen 141 a, icons associatedwith each application program executable by the mobile informationterminal 100 are displayed on the display unit 141. Selection of any oneof the icons causes a predetermined application program associated withthe selected icon to be executed.

Note that the icon may be selected through, for example, a tap operationon a predetermined area on the touch panel 130 t that corresponds to aposition on the display unit 141 at which the target icon is displayed.Alternatively, the icon may be selected with an operation key (notillustrated), such as a cross cursor key or an enter key. The icon maybe selected on the basis of line-of-sight information obtained by thefirst image input unit 143 that detects the line-of-sight of the user ofthe mobile information terminal 100.

In the mobile information terminal 100 that operates under the controlof the basic operation execution module 1101, selection of an icon 141 a1 on the basic screen 141 a through a user's operation such as a tapoperation causes the basic operation execution module 1101 to invoke theremote viewing execution module 1102 and transfer main control to theremote viewing execution module 1102. The transfer of the main controlmay be performed by, for example, an invocation of a program subroutine,and the basic operation execution module 1101 may operate in thebackground after the transfer of the main control. Note that the icon141 a 1 is an icon associated with an application program that executesthe remote viewing function on the mobile information terminal 100 ofthe present example.

An example of operations performed during the execution of the remoteviewing function of the mobile information terminal 100 under thecontrol of the remote viewing execution module 1102 will be describedbelow with reference to the operation sequence in FIG. 4 .

The selection of the icon 141 a 1 on the basic screen 141 a through auser's operation such as a tap operation starts the remote viewingfunction of the mobile information terminal 100 (S101). Next, the remoteviewing execution module 1102 to which the main control has beentransferred from the basic operation execution module 1101 by theinvocation of the remote viewing function displays a program typeselection screen 141 b on the display unit 141.

FIG. 5B is a screen display diagram illustrating an example of theprogram type selection screen 141 b displayed on the display unit 141 ofthe mobile information terminal 100. With the remote viewing function ofthe mobile information terminal 100 of the present example, it ispossible to perform live viewing of a digital broadcast program receivedby the tuner/demodulator 431 of the broadcast receiver 400 and viewingof recorded content stored in the storage unit 410 by the broadcastreceiver 400. The program type selection screen 141 b displays aselection icon 141 b 1 for performing the live viewing of a digitalbroadcast program and a selection icon 141 b 2 for performing theviewing of recorded content. In the following, a case where the liveviewing of a digital broadcast program is performed will be described.

Selection of the icon 141 b 1 on the program type selection screen 141 bthrough a user's operation such as a tap operation (S102) causes theremote viewing execution module 1102 to first transmit, to the broadcastreceiver 400 with which the mobile information terminal 100 is paired inadvance, an operational state check request for checking an operationalstate of the broadcast receiver 400 (S103). The pairing may be performedas appropriate through an authentication process in advance between themobile information terminal 100 and the broadcast receiver 400 via anetwork constructed by the router 200 r in a house in which thebroadcast receiver 400 is installed. The mobile information terminal 100stores the result of the authentication process in an authenticationinformation storage area 1012 of the storage unit 110. Note that theauthentication process may be performed by any known technique.

The broadcast receiver 400 that has received the operational state checkrequest from the mobile information terminal 100 checks an operationalstate of each component in the broadcast receiver 400 (S104). That is,the broadcast receiver 400 checks the operational state of each of thehardware and software components to determine whether or not the remoteviewing function is ready to be executed on the mobile informationterminal 100. The broadcast receiver 400 returns the result of theoperational state check to the mobile information terminal 100.

The remote viewing execution module 1102 of the mobile informationterminal 100 obtains the result of the operational state check from thebroadcast receiver 400 (S105). The remote viewing execution module 1102then refers to the obtained operational state of the broadcast receiver400 to determine whether or not the remote viewing function is ready tobe executed (S106). When the broadcast receiver 400 is in use by anotherin-house user and particularly, for example, the function of the tuner431 or the code converter 440 is not available, the remote viewingexecution module 1102 determines that the remote viewing function is notready to be executed. In S105, when, for example, the result of theoperational state check cannot be obtained from the broadcast receiver400, the remote viewing execution module 1102 may also determine thatthe remote viewing function is not ready to be executed. Whendetermining that the remote viewing function is not ready to be executedin S106 (S106: NG), the remote viewing execution module 1102 returns themain control to the basic operation execution module 1101 and terminatesits operation (S118).

In contrast, when determining that the remote viewing function is readyto be executed in S106 (S106: OK), the remote viewing execution module1102 then transmits a program information transmission request to thebroadcast receiver 400 (S107). The broadcast receiver 400 that hasreceived the program information transmission request from the mobileinformation terminal 100 returns the program information data row outputfrom the demultiplexer 432 to the mobile information terminal 100 asprogram information. Upon obtaining the program information returnedfrom the broadcast receiver 400 in response to the program informationtransmission request (S108), the remote viewing execution module 1102 ofthe mobile information terminal 100 displays a program guide screen 141c created on the basis of the obtained program information on thedisplay unit 141 (S109).

FIG. 5C is a screen display diagram illustrating an example of theprogram guide screen 141 c displayed on the display unit 141 of themobile information terminal 100. The program guide screen 141 c is atable showing broadcast programs to be distributed in a digitalbroadcast service. The table is created by the remote viewing executionmodule 1102 on the basis of the program information obtained from thebroadcast receiver 400. In the present example, the program guide screen141 c shows detailed information on each broadcast program that isbroadcast in each time slot on each channel, the information beingarranged in a matrix in which the vertical axis represents time and thehorizontal axis represents service ID (channel).

The program guide screen 141 c may only show detailed information onbroadcast programs that are currently being broadcast on respectivechannels. Furthermore, the program guide screen 141 c may be displayedin such a way that only the broadcast programs that are currently beingbroadcast can be selected. Moreover, as an alternative to S107 and S108,the remote viewing execution module 1102 of the mobile informationterminal 100 may obtain the program information directly from a programinformation distribution server (not illustrated) on the Internet 200via the mobile phone network communication unit 122.

Next, a process of selecting a broadcast program that the user wishes toview is performed by using the remote viewing function (S110). Theprocess of selecting a broadcast program that the user wishes to viewmay be performed, on the program guide screen 141 c displayed on thedisplay unit 141 in S109, by detecting a tap operation on apredetermined area on the touch panel 130 t corresponding to an area inwhich detailed information on the broadcast program that the user wishesto view is displayed (an area 141 c 1 in the example illustrated in FIG.5C) or the like.

After the process of selecting a broadcast program is performed inresponse to an operation by the user of the mobile information terminal100, the communication management execution module 1103 performs aprocess of checking a data communication state of the mobile informationterminal 100 under the control of the remote viewing execution module1102 (S111). For example, in the process of checking a datacommunication state, a data communication amount check module 1103 a ofthe communication management execution module 1103 performs a process ofchecking the total data communication amount of the mobile informationterminal 100 through mobile phone network communication in apredetermined period. Furthermore, according to the result of theprocess of checking a data communication state, the remote viewingexecution module 1102 displays, on the program guide screen 141 c, aremote image quality selection box 141 c 2 for prompting the user toselect a viewing image quality of the broadcast program during remoteviewing.

FIG. 5D is a screen display diagram illustrating an example of theremote image quality selection box 141 c 2 displayed on the programguide screen 141 c. For the mobile information terminal 100 of thepresent example, a viewing image quality during remote viewing can beselected from three types of viewing image qualities, namely, 720p,360p, and 180p. In this configuration, three types of setting values,720p, 360p, and 180p, are displayed in the remote image qualityselection box 141 c 2 in such a way that the setting values areappropriately selectable.

The details of the above-described processes of checking the total datacommunication amount through mobile phone network communication in apredetermined period and displaying the remote image quality selectionbox 141 c 2 on the program guide screen 141 c on the basis of the checkresult will be described later.

After the process of selecting a viewing image quality during remoteviewing is performed in response to an operation by the user of themobile information terminal 100 (S112), the remote viewing executionmodule 1102 then transmits, to the broadcast receiver 400, programidentification information with which the broadcast program selected inS110 can be identified and the setting value of the viewing imagequality selected in S112 (S113).

After receiving the program identification information and the settingvalue of the viewing image quality from the mobile information terminal100, the broadcast receiver 400 controls the tuner/demodulator 431 onthe basis of the received program identification information to select achannel for the broadcast program specified in the programidentification information (S114). Furthermore, the broadcast receiver400 inputs a TS of the broadcast program output from thetuner/demodulator 431 to the code converter 440 via the demultiplexer432, and the code converter 440 performs a transcoding process thatcorresponds to the setting value of the received viewing image quality(S115). That is, when the user of the mobile information terminal 100selects 360p as a viewing image quality during remote viewing in S112,the code converter 440 transcodes 1080i video data of digital broadcastinto the selected 360p video data, for example. The broadcast programdata output from the code converter 440 is distributed to the mobileinformation terminal 100 via the LAN communication unit 421.

The remote viewing execution module 1102 of the mobile informationterminal 100 obtains the broadcast program data distributed from thebroadcast receiver 400 in response to the transmission of the programidentification information and the setting value of the viewing imagequality (S116). Furthermore, the content playback execution module 1104performs, as appropriate, necessary processes such as decoding theobtained broadcast program data under the control of the remote viewingexecution module 1102 and displays the broadcast program data as aremote viewing screen 141 d on the display unit 141 via the image signalprocessor 142 (S117).

FIG. 5E is a screen display diagram illustrating an example of theremote viewing screen 141 d displayed on the display unit 141 of themobile information terminal 100. The remote viewing screen 141 d is aviewing screen when live viewing of a digital broadcast program, whichhas been received by the in-house broadcast receiver 400, is performedaway from home on the mobile information terminal 100 via the Internet200. A control icon 141 d 1 is an icon for an operation such asterminating remote viewing or changing a channel.

When the remote viewing is stopped by a user's operation on the controlicon 141 d 1 or when the broadcast program being viewed ends and theremote viewing stops automatically, the remote viewing execution module1102 returns the main control to the basic operation execution module1101 and terminates its operation (S118). Note that the remote viewingexecution module 1102 may continue its operation without terminationthereof and display the program type selection screen 141 b on thedisplay unit 141 to prompt the user to select to perform the liveviewing of a digital broadcast program again or the viewing of recordedcontent. This configuration only requires the operation to make atransition to S102 of the operation sequence in FIG. 4 . Alternatively,the remote viewing execution module 1102 may display the program guidescreen 141 c on the display unit 141 and prompt the user to select abroadcast program again. This configuration only requires the operationto make a transition to S107 of the operation sequence in FIG. 4 .

When the user selects, in S102, to perform the viewing of recordedcontent stored in the storage unit 410 of the broadcast receiver 400, itis only required that a transmission request for recorded content listinformation be transmitted to the broadcast receiver 400 in S107.Furthermore, in S108 and S109, it is only required that the recordedcontent list information transmitted from the broadcast receiver 400 beobtained and a recorded content list be created from the obtainedrecorded content list information and displayed on the display unit 141.Moreover, in S114, it is only required that a process of readingpredetermined recorded content from the storage unit 410 be performed onthe basis of identification information on the recorded contenttransmitted from the mobile information terminal 100.

Next, the processes of S111 and S112 will be described in detail.

Note that, with the limitation on communication speed imposed by themobile phone carrier for the mobile information terminal 100 of thepresent example, the data communication speed is not limited (that is,for example, high-speed data communication of 75 Mbps is possible) whilethe total data communication amount in a month is less than or equal to7.0 GB, and the data communication speed is limited to a lower speed(for example, less than or equal to 128 kbps) once the total datacommunication amount in the month exceeds 7.0 GB. Furthermore, on themobile information terminal 100 of the present example, a viewing imagequality during remote viewing (hereinafter referred to as a “remoteviewing image quality”) can be selected from three types of remoteviewing image qualities, 720p, 360p, and 180p as described above.Respective communication bands required for the remote viewing imagequalities are about 4.0 Mbps, about 1.5 Mbps, and about 700 kbps.

These remote viewing image qualities may be used as viewing imagequalities that can be transcoded by the code converter 440 of thebroadcast receiver 400 and viewing image qualities which the mobileinformation terminal 100 supports. For example, the mobile informationterminal 100 may obtain information relating to viewing image qualitiesthat can be transcoded by the broadcast receiver 400 in S105 and comparethese viewing image qualities with viewing image qualities that can bedisplayed by the mobile information terminal 100. The mobile informationterminal 100 may obtain communication band information from thebroadcast receiver 400 in S105 because the value of the communicationband corresponding to each remote viewing image quality depends on whatis converted by the code converter 440.

Selection of the 720p as a remote viewing image quality requires datatransfer of about 1.47 GB to receive one-hour video data. That is, whenthe user selects the 720p as a remote viewing image quality, video datareception through high-speed data communication can be performed foronly about 4.7 hours. When the user selects the 360p as a remote viewingimage quality, to receive one-hour video data requires a datacommunication amount of about 0.55 GB, and the video data receptionthrough high speed data communication can be performed for about 12.7hours. When the user selects the 180p as a remote viewing image quality,to receive one-hour video data requires a data communication amount ofabout 0.27 GB, and the video data reception through high speed datacommunication can be performed for about 25.9 hours.

FIG. 6A is a schematic diagram illustrating an example of a process ofcontrolling the remote viewing image quality according to the total datacommunication amount through mobile phone network communication in apredetermined period (in a month).

In the present example, two thresholds, namely, a first predeterminedvalue (for example, 4.0 GB) and a second predetermined value (forexample, 5.5 GB) are set for the total data communication amount (forexample, 7.0 GB) up to which high-speed data communication is possible.The remote viewing image quality selectable by the user is controlledaccording to the result of comparing the data communication amount in apredetermined period (in a month) up to the time of viewing with thefirst predetermined value and the second predetermined value.Specifically, in S111, the data communication amount check module 1103 aof the communication management execution module 1103 checks thecumulative data communication amount of the mobile information terminal100 through mobile phone network communication in a predetermined period(in a month) up to the time of viewing (hereinafter referred to as a“particular point in time”).

(a) When the cumulative data communication amount is less than or equalto the first predetermined value, the remote viewing execution module1102 performs the control in such a way that any one of the remoteviewing image qualities of the 720p, 360p, and 180p can be selected inS112. (b) When the cumulative data communication amount is more than thefirst predetermined value and less than or equal to the secondpredetermined value, the remote viewing execution module 1102 performsthe control in such a way that one of the remote viewing image qualitiesof the 360p and 180p can be selected in S112. (c) When the cumulativedata communication amount is more than the second predetermined value,the remote viewing execution module 1102 performs the control in such away that only the remote viewing image quality of the 180p can beselected in S112.

Basically, the particular point in time is the time of viewing, andparticularly, the time when the viewing is started. However, theparticular point in time may not be strictly limited to the time whenthe viewing is started because the viewing is started after the datacommunication amount is subjected to comparison and the remote viewingimage quality is selected. The particular point in time may be, forexample, the time of execution of S111, a certain time of the day whenthe cumulative data communication amount before the execution of S111 iscalculated, or a time of the day when the data communication amount upto the day before the execution of S111 is totaled.

Note that the above-described process of checking the cumulative datacommunication amount of the mobile information terminal 100 throughmobile phone network communication in a predetermined period (in amonth) may be performed as follows: causing the data communicationamount check module 1103 to transmit identification information withwhich the mobile information terminal 100 can be identified to themobile phone communication server 300; and causing the mobile phonecommunication server 300 to obtain a value corresponding to thecumulative data communication amount of the mobile information terminal100. Alternatively, the process may be performed as follows: causing thebasic operation execution module 1101 of the mobile information terminal100 to operate in the background during data communication and toaccumulate, in the storage unit 110 or the like, the data communicationamount each time the data communication is performed through the mobilephone network communication unit 122; and causing the data communicationamount check module 1103 to obtain the accumulation value, or othermethods may be used.

Such a control makes it possible to reduce the likelihood of using upthe data capacity within which high-speed data communication is possibledue to successive selection of a higher remote viewing image qualitywhen the remote viewing function is used and thereby making thesubsequent use of service inconvenient. That is, it becomes possible toprovide a mobile information terminal that provides high usability whencontent viewing is performed.

There may be a case where the above-described communication capacitywithin which high-speed data communication is possible in apredetermined period (in a month) differs among mobile phone carriers.In this case, control may be performed in such a way that thecommunication management execution module 1103 changes the firstpredetermined value and the second predetermined value depending on amobile phone carrier to which a subscription has been made.Specifically, for example, (a) when the mobile information terminal 100is used under the subscription to a mobile phone carrier A, the firstpredetermined value and the second predetermined value are set to 3.0 GBand 5.0 GB, respectively. (b) When the mobile information terminal 100is used under the subscription to a mobile phone carrier B, the firstpredetermined value and the second predetermined value are set to 4.0 GBand 5.5 GB, respectively. (c) When the mobile information terminal 100is used under the subscription to a mobile phone carrier C, the firstpredetermined value and the second predetermined value are set to 5.0 GBand 6.0 GB, respectively.

Note that the user may perform change control of the first predeterminedvalue and the second predetermined value in, for example, a setting menuof the mobile information terminal 100 each time the mobile phonecarrier to which the subscription has been made is changed.Alternatively, after the connection state of a subscriber identifymodule (SIM) card and the like (not illustrated) associated with thestate of subscription to each mobile phone carrier is detected, thechange control may be automatically performed according to the detectedSIM card and the like. Each predetermined value used for the changecontrol may be pre-stored in the mobile information terminal 100 as areference table or may be obtained from the mobile phone communicationserver 300 or a database server (not illustrated) on a network each timethe change control is performed. The change control may be performedaccording to each predetermined value stored in the SIM card and thelike. This control may be performed by the communication managementexecution module 1103.

Note that when the above-described communication capacity within whichhigh-speed data communication is possible in a predetermined period (ina month) set by the mobile phone carrier is a sufficiently large amountor the mobile phone carrier does not impose a limitation on thecommunication speed, it goes without saying that the first predeterminedvalue and the second predetermined value may not be set and all of theremote viewing image qualities may be made selectable. Furthermore, thenumber of predetermined values is not limited to two and one or morethan two predetermined values may be set.

Such a control makes it possible to reduce the likelihood of using upthe data capacity within which high-speed data communication is possibledue to successive selection of a higher remote viewing image qualitywhen the remote viewing function is used and thereby making thesubsequent use of service inconvenient. That is, it becomes possible toprovide a mobile information terminal that provides high usability whencontent viewing is performed.

FIG. 6B is a schematic diagram illustrating an example, which isdifferent from the above example, of a process of controlling the remoteviewing image quality according to the total data communication amountthrough mobile phone network communication in a predetermined period (ina month). In this example, the data communication amount managementmodule 1103 a of the communication management execution module 1103checks the cumulative data communication amount of the mobileinformation terminal 100 through mobile phone network communication upto a particular point in time in a predetermined period (in a month)while the data communication period management module 1103 b of thecommunication management execution module 1103 checks elapsed time up tothe particular point in time in the predetermined period (in a month) inS111. According to these results, the remote viewing image qualityselectable by the user is controlled.

That is, as illustrated in FIG. 6B, the communication managementexecution module 1103 checks elapsed time up to a particular point intime in the predetermined period (in a month), and (a) from the firstday to the 10th day of each month, the first predetermined value and thesecond predetermined value are set to 3.0 GB and 5.0 GB, respectively.(b) From the 11th day to the 20th day, the first predetermined value andthe second predetermined value are set to 4.0 GB and 5.5 GB,respectively. (c) From the 21st day to the end of the month, the firstpredetermined value and the second predetermined value are set to 5.0 GBand 6.0 GB, respectively. Note that the control may be performed usingsmaller units of time for the elapsed date and time. Furthermore, theelapsed time may be set by the user from, for example, a setting menu ofthe mobile information terminal 100 or may be obtained from the mobilephone communication server 300 or a database server (not illustrated).

Similar to the case where only the above-described control in FIG. 6A isperformed, such a control makes it possible to reduce the likelihood ofusing up the data capacity within which high-speed data communication ispossible due to successive selection of a higher remote viewing imagequality when the remote viewing function is used and thereby making thesubsequent use of service inconvenient. Furthermore, the control makesit possible to distribute, in the predetermined period, the use of thedata capacity within which high-speed data communication is possible.Moreover, the control makes it possible to reduce the likelihood of notusing up, by the end of the predetermined period, the data capacitywithin which high-speed data communication is possible. Therefore, itbecomes possible to efficiently use high-speed data communicationaccording to the elapsed time in the predetermined period. That is, itbecomes possible to provide a mobile information terminal that provideshigh usability when content viewing is performed.

FIG. 7A is a diagram illustrating an example of display format of theremote image quality selection box 141 c 2 displayed on the programguide screen 141 c. In this example, when the control described in FIG.6A is performed to prompt the user to select a remote viewing imagequality, the display format of the remote image quality selection box141 c 2 is controlled according to the result of comparing the datacommunication amount up to a particular point in time in a predeterminedperiod (in a month), which has been checked by the data communicationamount check module 1103 a of the communication management executionmodule 1103, with the first predetermined value and the secondpredetermined value.

Specifically, the data communication amount check module 1103 a of thecommunication management execution module 1103 checks the cumulativedata communication amount of the mobile information terminal 100 throughmobile phone network communication up to a particular point in time in apredetermined period (in a month). (a) When the cumulative datacommunication amount is less than or equal to the first predeterminedvalue, the remote image quality selection box 141 c 2 is displayed in adisplay format as illustrated in (a) of FIG. 7A. (b) When the cumulativedata communication amount is more than the first predetermined value andis less than or equal to the second predetermined value, the remoteimage quality selection box 141 c 2 is displayed in a display format asillustrated in (b) of FIG. 7A. (c) When the cumulative datacommunication amount is more than the second predetermined value, theremote image quality selection box 141 c 2 is displayed in a displayformat as illustrated in (c) of FIG. 7A.

In the displays in FIGS. 7A and 7B, circles at the left of remoteviewing image quality values are so-called unselected radio buttons. Theselection of a remote viewing image quality through a tap (click)operation on one of the radio buttons may be detected or the selectionmay be detected as a selection confirmed through an operation by theuser after one of the radio buttons is tapped (clicked). Such a controlallows the user, upon selecting a remote viewing image quality, toselect only an appropriate remote viewing image quality corresponding toa data communication amount through mobile phone network communicationup to a particular point in time in a predetermined period (in a month).That is, it becomes possible to provide a mobile information terminalthat provides high usability when content viewing is performed.

FIG. 7B is a diagram illustrating an example, which is different fromthe above example, of display format of the remote image qualityselection box 141 c 2 displayed on the program guide screen 141 c. Inthis example, when the user is prompted to select a remote viewing imagequality under control partially changed from the control described inFIG. 7A, selectable remote viewing image qualities are not limited.Furthermore, the initial selection position of the remote image qualityselection box 141 c 2 is controlled according to the result of comparingthe data communication amount up to a particular point in time in apredetermined period (in a month), which is checked by the datacommunication amount check module 1103 a of the communication managementexecution module 1103, with the first predetermined value and the secondpredetermined value.

Specifically, the data communication amount check module 1103 a of thecommunication management execution module 1103 checks the cumulativedata communication amount of the mobile information terminal 100 throughmobile phone network communication up to a particular point in time in apredetermined period (in a month). (a) When the cumulative datacommunication amount is less than or equal to the first predeterminedvalue, the initial selection position is set to a remote viewing imagequality of 720p among three selectable remote viewing image qualities,as illustrated in (a) of FIG. 7B. (b) When the cumulative datacommunication amount is more than the first predetermined value and isless than or equal to the second predetermined value, the initialselection position is set to a remote viewing image quality of 360pamong three selectable remote viewing image qualities, as illustrated in(b) of FIG. 7B. (c) When the cumulative data communication amount ismore than the second predetermined value, the initial selection positionis set to a remote viewing image quality of 180p among three selectableremote viewing image qualities, as illustrated in (c) of FIG. 7B.

A black dot in a radio button at the left of a remote viewing imagequality value in FIG. 7B indicates an initial selection position. Theblack dot of the initial selection position can be moved when one of theradio buttons is tapped (clicked). Additionally, the selection may beconfirmed by a certain user operation, and it may be detected that theconfirmed remote viewing image quality at the right of the black dot,which includes the initial selection position, is selected.

Similar to the case where the above-described control in FIG. 7A isperformed, such a control allows the user, upon selecting a remoteviewing image quality, to select only an appropriate remote viewingimage quality corresponding to the total data communication amountthrough mobile phone network communication in a predetermined period (ina month). Furthermore, such a control allows the user to select any oneof the remote viewing image qualities that can be selected by the remoteviewing function of the mobile information terminal 100. That is, itbecomes possible to provide a mobile information terminal that provideshigh usability when content viewing is performed.

Note that when the control described in FIG. 7B is performed and theuser selects a remote viewing image quality that is higher than theremote viewing image quality of the initial selection position, awarning message or the like may be displayed on the display unit 141.Specifically, for example, when the remote image quality selection box141 c 2 is displayed in the display format illustrated in (b) of FIG. 7B(in which the initial selection position is 360p) and the user selects720p as a remote viewing image quality, a message such as “720p has beenselected. Are you sure you want to perform remote viewing with thisimage quality?” is displayed on the display unit 141. This makes itpossible to prevent the data communication capacity from being wasteddue to an operation error by the user or the like by confirming theuser's intention again when the user selects a high remote viewing imagequality that is not recommended by the mobile information terminal 100.

Alternatively, control may be performed in such a way that the user isinhibited from selecting a remote viewing image quality and the remoteviewing image quality is automatically determined according to theresult of comparing the data communication amount up to a particularpoint in time in a predetermined period (in a month), which is checkedby the data communication amount check module 1103 a of thecommunication management execution module 1103, with the firstpredetermined value and the second predetermined value. In this case,S112 in FIG. 4 is not needed.

Specifically, the data communication amount check module 1103 a of thecommunication management execution module 1103 first checks thecumulative data communication amount of the mobile information terminal100 through mobile phone network communication up to a particular pointin time in a predetermined period (in a month). (a) When the cumulativedata communication amount is less than or equal to the firstpredetermined value, the 720p is selected as a remote viewing imagequality, and, in S113 of the operation sequence in FIG. 4 , the settingvalue corresponding to the selected remote viewing image quality istransmitted to the broadcast receiver 400. (b) When the cumulative datacommunication amount is more than the first predetermined value and isless than or equal to the second predetermined value, the 360p isselected as a remote viewing image quality, and, in S113 of theoperation sequence in FIG. 4 , the setting value corresponding to theselected remote viewing image quality is transmitted to the broadcastreceiver 400. (c) When the cumulative data communication amount is morethan the second predetermined value, the 180p is selected as a remoteviewing image quality, and, in S113 of the operation sequence in FIG. 4, the setting value corresponding to the selected remote viewing imagequality is transmitted to the broadcast receiver 400.

During remote viewing that has been started, when the cumulative datacommunication amount up to a particular point in time in a predeterminedperiod (in a month) exceeds one of the predetermined values, control maybe performed in such a way that the remote viewing image quality ischanged in the middle of the remote viewing. When the remote viewingimage quality is changed, a message may be displayed on the display unit141 indicating that the change has been completed. Alternatively, theremote viewing image quality may be changed after displaying a messagefor confirming the change on the display unit 141 and detecting acertain user operation.

Similar to the case where only the above-described control in FIG. 6A isperformed, such a control makes it possible to reduce the likelihood ofusing up the data capacity within which high-speed data communication ispossible due to successive selection of a higher remote viewing imagequality when the remote viewing function is used and thereby making thesubsequent use of service inconvenient. Furthermore, such a controlallows the user to omit selection of a remote viewing image quality.That is, it becomes possible to provide a mobile information terminalthat provides high usability when content viewing is performed.

FIG. 8 is a screen display diagram illustrating a display example of aremote image quality selection box 141 c 3 displayed on the programguide screen 141 c, which is different from the display example of theremote image quality selection box 141 c 2 illustrated in FIG. 5D. Theremote image quality selection box 141 c 3 is configured to control aremote viewing image quality that can be selected by a user so as to bedisplayed with remaining viewable times provided when each of the remoteviewing image qualities is selected.

Note that the remaining viewable time can be calculated by dividing aremaining amount of high-speed data communication by a communicationband value needed for each remote viewing image quality. The remainingamount of high-speed data communication is obtained as the differencebetween the cumulative data communication amount of the mobileinformation terminal 100 through mobile phone network communication upto a particular point in time in a predetermined period (in a month),and the total data communication amount up to which high-speedcommunication is possible for each predetermined period (for eachmonth). Both the cumulative amount and the total amount are checked bythe data communication amount check module 1103 a of the communicationmanagement execution module 1103.

The display of the remaining viewable time may be applied to the displayillustrated in FIG. 7A or may be applied to the display illustrated inFIG. 7B. Such a control allows the user to check, upon selecting aremote viewing image quality, the remaining viewable time within whichhigh-speed data communication is possible. That is, it becomes possibleto provide a mobile information terminal that provides high usabilitywhen content viewing is performed.

Note that in the above description, the example has been described inwhich the data transmission and reception between the mobile informationterminal 100 and the Internet 200 is performed by the mobile phonenetwork communication unit 122 via the mobile phone communication server300 and the base station 300 b, and the data communication functionprovided by the mobile phone carrier, the mobile information terminal100 being under the subscription thereof, has a capability to impose alimitation on communication speed. However, examples are not limited tothe example described above. For example, in the case where the datatransmission and reception between the mobile information terminal 100and the Internet 200 is performed by the LAN communication unit 121 viathe access point 200 a, the above-described control may be applied todata communication with a members-only content distribution server (notillustrated) or the like in which the total download capacity therefromin each predetermined period (in each month) is limited. That is, theabove-described control may be applied to both cases where a datacommunication channel has a limitation on the total data capacitythereof and where a server itself has a limitation on the total downloadcapacity therefrom.

Some examples have been described above, but it goes without saying thatconfigurations realizing the control described above are not limited tothese examples and various modifications are contemplated. For example,some of the components may be replaced with other components, andnumeric values, messages, and the like that appear in the descriptionsor figures are merely examples. Thus, the use of different values,messages, and the like does not impair the effect.

The above-described functions and the like may be implemented ashardware by, for example, designing some or all of the functions and thelike for an integrated circuit. Alternatively, the functions and thelike may be implemented as software by using a microprocessor unit orthe like interpreting and executing an operation program that realizeseach of the functions and the like. The functions and the like may beimplemented by using both hardware and software.

Note that the software that controls the mobile information terminal 100may be pre-stored in, for example, the ROM 103 and/or the storage unit110 of the mobile information terminal 100 before product shipment. Thesoftware may be obtained from the additional application server 500 orthe like on the Internet 200 via the LAN communication unit 121 or themobile phone network communication unit 122 after product shipment.Furthermore, the software stored in, for example, a memory card oroptical disc may be obtained via the extended interface 124 or the like.

REFERENCE SIGNS LIST

-   100 Mobile information terminal-   101 Main controller-   102 System bus-   103 ROM-   104 RAM-   110 Storage unit-   120 Communication processor-   124 Extended interface-   130 Operation unit-   140 Image processor-   150 Audio processor-   160 Sensor-   200 Internet-   200 a Access point-   200 r Router-   300 Mobile phone communication server-   300 b Base station-   400 Broadcast receiver-   400 a Antenna-   400 t Broadcasting tower-   500 Additional application server

1. A mobile information terminal communication method, comprising:performing data transmission and reception including, video datareception of video data, to/from an outside of a mobile informationterminal; obtaining, from the outside, a total data communication amountindicating a limit capable of high-speed communication by the mobileinformation terminal within a predetermined period; setting apredetermined value, which is determined based on the obtained totaldata communication amount and is less than the obtained total datacommunication amount, in accordance with a number of days elapsed from astart of the predetermined period; obtaining a cumulative datacommunication amount of data which has been transmitted and received bythe communication processor from the start of the predetermined periodto a viewing start point of the video data; upon determining thecumulative data communication amount exceeds the predetermined value,display a selection screen on a display where two or more imagequalities are selectable on the display as an image quality for thevideo data; after the image quality for the video data has beenselected, transmitting a setting value corresponding to the selectedimage quality to an external device storing the video data; receivingthe video data having the selected image quality from the externaldevice; and displaying the video data having the selected image qualityon the display.
 2. The mobile information terminal communication methodaccording to claim 1, wherein upon determining the cumulative datacommunication amount is less than or equal to the predetermined value,displaying the selection screen where three or more image qualities areselectable on the display as the image quality for the video data. 3.The mobile information terminal communication method according to claim2, wherein the three or more image qualities include the two or moreimage qualities and the three or more image qualities are preset in thememory.
 4. The mobile information terminal communication methodaccording to claim 3, further including: obtaining program informationor file information, wherein information of the video data is includedin the program information or file information.
 5. A mobile informationterminal communication method comprising: performing data transmissionand reception including, video data reception of video data, to/from anoutside of a mobile information terminal; obtaining, from the outside, atotal data communication amount indicating a limit capable of high-speeddata communication by the mobile information terminal within apredetermined period; obtaining a cumulative data communication amountof data which has been transmitted and received by the mobileinformation terminal from a start of the predetermined period to aviewing start point of the video data; obtaining an elapsed amount oftime from a start of the predetermined period; selecting one of aplurality of predetermined values, each of which is determined based onthe obtained total data communication amount and is less than theobtained total data communication amount, on the basis of the elapsedamount of time from the start of the predetermined period; upondetermining the cumulative data communication amount exceeds theselected predetermined value, displaying a selection screen on a displaywhere two or more image qualities are selectable on the display as animage quality for the video data; after the image quality for the videodata has been selected, transmitting a setting value corresponding tothe selected image quality to an external device storing the video data;receiving the video data having the selected image quality from theexternal device; and displaying the video data having the selected imagequality on the display.
 6. The mobile information terminal communicationmethod according to claim 5, wherein: upon determining the cumulativedata communication amount is less than or equal to the selectedpredetermined value, displaying the selection screen where three or moreimage qualities are selectable on the display as the image quality forthe video data.
 7. The mobile information terminal communication methodaccording to claim 6, wherein the three or more image qualities includethe two or more image qualities and the three or more image qualitiesare preset in the memory.
 8. The mobile information terminalcommunication method according to claim 7, further including: obtainingprogram information or file information, wherein information of thevideo data is included in the program information or file information.9. A mobile information terminal communication method comprising:performing data transmission and reception including, video datareception of video data, to/from an outside of a mobile informationterminal; obtaining, from the outside, a total data communication amountindicating a limit capable of high-speed communication by the mobileinformation terminal within a predetermined period; setting apredetermined value, which is determined based on the obtained totaldata communication amount and is less than the obtained total datacommunication amount, in accordance with a number of days elapsed from astart of the predetermined period; displaying on a display a programguide screen where a list of a plurality of video content are selectableon the display as the video data to be received; after the video data tobe received is selected, obtaining a cumulative data communicationamount of data which has been transmitted and received by the mobileinformation terminal from the start of the predetermined period to aviewing start point of the video data; upon determining the cumulativedata communication amount exceeds the predetermined value, displaying aselection box where two or more image qualities are selectable as animage quality for the video data in front of the program guide screendisplayed on the display; after the image quality for the video data hasbeen selected, transmitting a setting value corresponding to theselected image quality to an external device storing the video data;receiving the video data having the selected image quality from theexternal device; and displaying the video data having the selected imagequality on the display.
 10. The mobile information terminalcommunication method according to claim 9, further including: displayingthe selection box where respective numbers of display pixels orrespective numbers of display scanning lines of the video data are partof information on the two image qualities that are selectable as theimage quality for the video data.
 11. The mobile information terminalcommunication method according to claim 10, further including:displaying the selection box where respective viewable times are part ofinformation on the two image qualities that are selectable as the imagequality for the video data.
 12. The mobile information terminalaccording to claim 1, further including displaying the selection screenwhere respective viewable times are part of information on the two imagequalities that are selectable as the image quality for the video data.13. The mobile information terminal according to claim 5, furtherincluding displaying the selection box where respective viewable timesare part of information on the two image qualities that are selectableas the image quality for the video data.
 14. The mobile informationterminal communication method according to claim 1, wherein a higherimage quality is selectable when displaying the video data in a casewhere the number of days elapsed in the predetermined period is shorterthan in a case where the number of days elapsed in the determined periodis larger.
 15. The mobile information terminal communication methodaccording to claim 14, wherein a resolution of the video data isselectable as the image quality.
 16. The mobile information terminalcommunication method according to claim 1, wherein the predeterminedvalue is a first value when the number of days elapsed in thepredetermined period is in a first range, and the predetermined value isset to be a second value larger than the first value when the number ofelapsed days is in a second range larger than the first range.
 17. Themobile information terminal communication method according to claim 9,wherein a higher image quality is selectable when displaying the videodata in a case where the number of days elapsed in the predeterminedperiod is shorter than in a case where the number of days elapsed in thedetermined period is larger.
 18. The mobile information terminalcommunication method according to claim 17, wherein a resolution of thevideo data is selectable as the image quality.
 19. The mobileinformation terminal communication method according to claim 9, whereinthe predetermined value is a first value when the number of days elapsedin the predetermined period is in a first range, and the predeterminedvalue is set to be a second value larger than the first value when thenumber of elapsed days is in a second range larger than the first range.